Drying of artificial filaments



Patented July 19, 1932 UNITED STATES PATENT OFFICE RICHARD ELSSNEB, OF JOHNSON CITY, TENNESSEE, ASSIGNOR T AMERICAN GLANZ STOFF CORPORATION, OF NEW YORK, N. Y., A CORPORATION OF DELAWARE DRYING OF ARTIFICIAL FILAMENTS No Drawing.

My present invention has to do with a new and improved method for equalizing the shrinkage of freshly produced artificial filaments, produced according to the spool spinning method.

One object of my invention is to provide a yarn which possesses very even dyeing qualities due to the evenness of shrinkage occasioned by my special treatment.

Other objects will become apparent from a perusal of the following specification and of the appended claims.

Generally, in the spool spinning process, the yarn is spun 'onto rigid or collapsible perforated spools or bobbins. These spools or bobbins are then washed by the drip wash, vacuum, or pressure process, dried in a wrapped or unwrapped state, twisted either tightly or loosely, and then again wet and dried in a wrapped or unwrapped state.

It has been found that this process results in yarn which dries very unevenly due to the fact that the tension set up in different portions of the yarn body as the drying progresses exerts tensions which preclude an even shrinkage of the yarn.

This uneven shrinkage and the attendant Y difficulties arising therefrom do not result when my new process is used.

According to the present process, the yarn is spun on perforated bobbins which bobbins are washed by the drip wash, vacuum or pressure wash methods. -However, no quick drying is now used as the bobbins are dried in the open air for a period of time varying upon conditions, between from 2 to 36 hours.

This drying is only carried to that extent where there is 80% of moisture contents.

Then the yarn, still in a wet state, is wound upon disk spools, preferably perforated, in such a way that a loose yarn body is obtained. that is, no great amount of tension is applied during this rewinding. The yarn, 3:. still wet, on the disk spool is then either twisted inunediately, or after a period of time, for examplefl'llhours, onto a twisting bobbin .which is preferably perforated- This twisted yarn body should be as loose 60 as possible, that is, no more tension than abous manipulations and to contain a moisture twisting spool, and

Application filed February 26, 1932. Serial No. 595,427.

solutely necessary should be applied during the twisting operation. c

. This loose twisted yarn body will be found to have been partially dried by these vari- 6 content of from to It is now dried to about from 3 to 12% moisture content.

It'will be seen that the various manipulations of the yarn' while in the wet state and through the final loose twisting of the yarn body, the same is given a chance to thoroughly shrink. The rapidity of drying during the various operations may be regulated and aided through control of the air conditions as regards temperature relative to humidity, direction of the air flow, etc.

, Having now set forth my invention according to the patent statues, what I desire to claim is: I

1. In the production of artificial filaments with even shrinkage, the steps of spinning thev filaments on perforated bobbins, washing, drying the bobbin inthe open air until there remains approximately moisture Y content, rewinding these filaments onto perforated disk spools, so that a loose body is obtained, twisting after a short period onto a twisting bobbin, and drying the yarn to about a 342% moisture content.

2. In a process for treating spooledartificial filaments, the steps of wet treating the yarn body while it is. upon a spool, drying slowlv until the moisture content is reduced below 80%, rewinding loosely onto a; twisting spool, thereby reducing the moisture content somewhat, and then completing the nec-' essary drying while the yarn body is on the twisting spool.

g 3. In a process of the class described, the steps of spinning a cellulosic solution directly upon a spool, wet treating the yarn while thereupon, drying the yarn until the mois- ,ture content has been reduced to approximately 80%, rewinding the yarn onto a completing the drying thereof. I

In witness whereof I aflix my signature.

DR RICHARD ELSSNER. 

